I just got Lumia 920 for a week now and still trying to figure out a decent apps (I usually find these apps on Best Rated section) that don't drain the battery pretty fast in the background or while not in use. As some of the apps, even though, you have exit it, it will still run in the background and unable to block it. The only app that can be blocked is Nokia Drive Beta. And currently under the Advanced tab on the Background Tasks, I still have 7 apps running.
Any suggestion? T

Thanks a lot for the help

Does anybody uses WeChat? As I think this is a decent app but drain the battery pretty quick even I haven't used it at all. After I installed it, usually at night I unplugged the fully charged phone, and in the morning after 7 hours, it will still stay at 100%, but after I installed it, the next morning when I woke up, it has drained the battery to 83%. Gonna try it again tonight to see.